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Sentinel

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Product Info
How to Use
Ingredients
Customer Reviews
Q&A
Product Info

What is Sentinel?

Sentinel is the only monthly oral preventive that guards against heartworms, adult roundworms, adult hookworms, whipworms, and prevents the development of flea eggs. Sentinel requires a prescription from your veterinarian.

NOTE: Sentinel does not kill adult fleas. If you see fleas on your pet, use Capstar Flea Treatment Tablets to quickly kill adult fleas within 30 minutes of administration.

For:

Dogs and Puppies (4+ weeks of age, weighing 2+ lbs)

Benefits:

  • Comes in palatable flavored tabs
  • Easy to administer just once a month

How does Sentinel work?

Milbemycin oxime eliminates the tissue stage of heartworm larvae and the adult stage of hookworm, roundworm, and whipworm infestations. Lufenuron, the other active ingredient, is an insect development inhibitor that breaks the flea life cycle by inhibiting egg development. Lufenuron prevents most flea eggs from hatching or maturing into adults and thus prevents and controls flea populations by breaking the life cycle. Sentinel may be given along with Capstar Flea Treatment Tablets, which treats flea infestation and kills adult fleas.

Cautions:

Side effects are rare, though some pets may exhibit vomiting, depression, drowsiness, itching, hives, loss of appetite, diarrhea, or seizures, hypersalivation, and weakness. If these or other symptoms develop contact your veterinarian. It's important to maintain good personal hygiene, since humans can contract hookworms and roundworms. It's also important to eliminate fleas and to not feed your pet rodents or uncooked meat or fish. To prevent re-infection, clean up stools on a daily basis. Consult your veterinarian for pregnant or lactating dogs.

Brand Name:

Sentinel (Virbac)

Generic Name:

Milbemycin Oxime (mil-beh-my-sin ox-eem) and Lufenuron (lew-fen-your-on)

What is the most important information I should know about Sentinel?

Sentinel is a prescription medication FDA-approved for use in dogs. Sentinel is available as artificial beef flavored (derived from pork and soy protein) chewable tablets. This medication should be given once a month year-round.

What should I discuss with my veterinarian before giving Sentinel to my pet?

Tell your veterinarian if your pet has ever had an allergic reaction to the medication.

How should Sentinel be given?

Give Sentinel exactly as directed by your veterinarian. If you do not understand the directions ask your pharmacist or veterinarian to explain them to you. The usual dose of Sentinel for dogs 2 to 10 pounds is 1 Flavor Tab every month (Brown Box), 11 to 25 pounds is 1 Flavor Tab every month (Green Box), 26 to 50 pounds is 1 Flavor Tab every month (Yellow Box) and 51 to 100 pounds is 1 Flavor Tab every month (White Box). For dogs over 100 pounds give the appropriate combination of tablets. To ensure adequate absorption, always administer Sentinel to dogs immediately after or in conjunction with a normal meal. Heartworm testing should be performed prior to the start of prevention therapy. If your pet is off Sentinel for 6 months or less, re-start the medication and test after 6 months since microfilaria, that take 6 months to mature, will result in a positive test result. Store Sentinel in a dry place at controlled room temperature, between 59-77F (15-25 C). Do not remove the tablet from its wrapper until ready to give the medicine. Keep this medication away from children and pets. Consult your veterinarian for pregnant or lactating dogs.

What are the possible side effects of Sentinel?

Side effects of Sentinel are rare although some pets may exhibit vomiting, depression, drowsiness, itching, hives, loss of appetite, diarrhea, or seizures, hypersalivation, and weakness. If these or other symptoms develop contact your veterinarian.

What happens if I miss giving a dose of Sentinel?

If a dose is missed and a 30-day interval between dosing is exceeded, administer Sentinel immediately and resume the monthly dosing schedule. If Sentinel replaces daily diethylcarbamazine (DEC) for heartworm prevention, the first dose must be given within 30 days after the last dose of DEC.

What happens if I overdose my pet on Sentinel?

Contact your veterinarian immediately.

What should I avoid while giving Sentinel to my pet?

Because humans can contract hookworms and roundworms from pets, it is important to maintain good personal hygiene. It is also important to eliminate fleas on your pet and in the household.

What other drugs will affect Sentinel?

While Sentinel is safe to use in dogs at risk for MDRI-allele mutation (Australian Shepherds, Collies, Shelties, etc.), unless tested normal, caution is advised if your pet is also being given amiodarone (Cordarone), azole antifungals such as ketoconazole, carvedilol (Coreg), cyclosporine (Atopica), diltiazem (Cardizem), erythromycin (Ery-Tabs) or clarithromycin (Biaxin), quinidine, spironolactone (Aldactone), tamoxifen, and verapamil (Calan). Do not give Sentinel to your pet if already giving an alternate heartworm medication.

How to Use

Sentinel Directions:

  • Give Sentinel Flavor Tabs once a month on the same day of each month year-round.
  • Sentinel Flavor Tabs is for use in dogs only. Do not give to cats.
  • Watch your dog closely following dosing to be sure the entire dose has been swallowed. If it is not completely swallowed, give one more full recommended dose as soon as possible.
  • To ensure adequate absorption, always administer Sentinel to dogs immediately after or in conjunction with a normal meal.
  • Sentinel has no effect on adult fleas, but controls flea populations by breaking the flea life cycle at the egg stage.
  • To speed control of flea infestation, products that kill adult fleas like Capstar Flea Treatment Tablets may be used temporarily with Sentinel depending on the severity of the infestation.
  • Treatment may begin at any time of the year.
  • It is important to treat all dogs in the household for fleas. Cats in the same household should be treated with approved products for heartworm prevention for cats.
Tip:

Do not remove Sentinel from its wrapper until ready to give to your pet.

Sentinel Dosage for Dogs/puppies: (4+ weeks of age, weighing 2+ lbs)

Dogs/puppies: (4+ weeks of age, weighing 2+ lbs)
WeightDosage
2-10 lbsGive 1 Flavor Tab every month (Brown Box)
11-25 lbsGive 1 Flavor Tab every month (Green Box)
26-50 lbsGive 1 Flavor Tab every month (Yellow Box)
51-100 lbsGive 1 Flavor Tab every month (White Box)
Over 100 lbsGive combination of Flavor Tabs based on weight
Sentinel Dosage for Cats:
Cats
Do not use!
Sentinel Dosage for Horses:
Horses
Do not use!
Storage:

Should be stored at room temperature between 59° and 77° F.

Ingredients

Sentinel for Dogs Ingredients:

Sentinel Brown for Dogs 2-10 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime2.3 mg
Lufenuron46 mg
Sentinel Green for Dogs 11-25 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime5.75 mg
Lufenuron115 mg
Sentinel Yellow for Dogs 26-50 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime11.5 mg
Lufenuron230 mg
Sentinel White for Dogs 51-100 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime23 mg
Lufenuron460 mg
Customer Reviews
Sentinel is rated 4.4 out of 5 by 788.
Rated 5 out of 5 by from Sentinel We have used Sentinel for many years, great product with good results
Date published: 2017-12-22
Rated 5 out of 5 by from Sentinel Sentinel is the only heartworm medication that did not cause stomach issues for our two dachshunds. Highly recommended for sensitive stomach dogs.
Date published: 2017-12-19
Rated 5 out of 5 by from Only medicine our dog can take Due to adverse allergic reactions to other heartworm preventative medecines, Sentinel, has been the only medication our sheltie can use. Fortunately, someone from work had recommended this and has saved ultimate aggravation. Sentinel has been a life saver!!!!
Date published: 2017-11-21
Rated 5 out of 5 by from Like the flavor I have been giving my furbabies Sentinel for years. It must taste good for them, they take it with no issues
Date published: 2017-11-17
Rated 5 out of 5 by from My babies Sentinel Sentinel is so good. Abbi loves it and it keeps her safe and it is affordable and is delivered in a matter of days and she loves the big bone you spoil her with.
Date published: 2017-11-08
Rated 5 out of 5 by from Fast Service! Love this product-my pet is protected! Easy to order, good sale price, and fast delivery right to the door---Griffin loves the biscuit in the box!
Date published: 2017-11-05
Rated 5 out of 5 by from A necessity A healthy dog is one that takes Sentinel, once a month! Though it may appear to be expensive but that is an investment that we dog lovers make to keep our pets going!
Date published: 2017-10-22
Rated 5 out of 5 by from Excellent Product! Trooper will be 2 years old in December. With vet approval, we put him on Sentinel when he was just a puppy. We have used the product for years with our Yellow Lab, with excellent results; and, when it was the proper time for Trooper to start this medication, we did not hesitate at all.
Date published: 2017-10-20
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Q&A

Do I need a perscriptson for flea medicine

Asked by: Davida
Thank you for your question. Sentinel guards against heartworms, adult roundworms, adult hookworms, whipworms, and prevents the development of flea eggs. Sentinel requires a prescription from your veterinarian.
Answered by: Crystal PetMed Pro
Date published: 2018-01-09

I ordered the sentinel 2-10 pound (2 packs of 6) what if my dog goes over 10 pounds will the medication be good?

Asked by: Tiffany
Since you weren't happy with the proper answer, if your dog goes over 10 pounds, to be fully protected, you would have to give 2 & 1/2 tablets each month of the size you purchased.
Answered by: SuzyCVT
Date published: 2018-01-03

Will Sentinel or 1-800 PetMeds reimburse for medical expenses if your dogs gets whipworm after months of giving them sentinel?

Asked by: Golden
Thank you for your question. We back all of our products with our "100% Happy Guarantee.  You're 100% happy or your money back!" 
Answered by: Crystal PetMed Pro
Date published: 2017-10-25

Is it safe to give my dogs Sentinel while they are wearing the Sorresto collar? I want to ensure they are safe to use in conjunction with one another. Thank you

Asked by: Kelbel
Yes, Sentinel may be safely administered while using a Seresto collar.
Answered by: Lisa M
Date published: 2017-10-11

My dog will not chew any flavored tab, He is picky about what treat or food he will eat in any given day, He obviously is a very picky eater, and eats a full meal maybe 1 time every 36 hours. Will this be effective. BTW he is a 16 lb shih tsu.

Asked by: Maxwill the picky one
Sentinel is a flavored tablet that is palatable to dogs. The majority of dogs will eat the chew when administered. The tablet may also be hidden in food if necessary but be sure the full dose is consumed. Sentinel is most effective when given with a meal.
Answered by: Lisa M
Date published: 2017-10-07

Can I give Advantage 11 for fleas to my dog and this Sentinel for heartworms at the same time....each once a month?

Asked by: Alice
There is no contraindication between Advantage II and Sentinel. They may be administered together.
Answered by: Lisa M
Date published: 2017-09-29

I have a MDR1 sensitive dog...is Sentinel safe for her?

Asked by: Oceangal
Yes, Sentinel is safe for use in MDR1 sensitive dogs.
Answered by: SuzyCVT
Date published: 2017-09-22

Do I need to have a prescription from my vet in order to get heartworm pills for my dog from you? In the past I've been getting them directly from the vet.

Asked by: Dian
Yes, a prescription is required for all heartworm preventatives.
Answered by: Lisa M
Date published: 2017-09-21
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